Portable adjustable chair



Oct. 1l, 1938. H. BURCHALL PORTABLE ADJUSTABLE CHAIR Filed Nov) 6, 1955 4 Sheets-Sheet l /M/f/vroe fram/Ey Oct. 11, 1938.

H. BURCHALL PORTABLE ADJUSTABLE CHAIR Filed Nov. 6,` 1955 4 Sheets-Sheet 2 oct. l1, 1938. H EURCHALL PORTABLE ADJUSTABLE CHAIR Filed Nov, 6', l1935 4 Sheets-Sheet 5 Oct. 11, 1938. H, BURCHALL 2,132,525

PORTABLE ADJUSTABLE CHAIR Filed Nov. e, 1935 1 sheets-sheet 4 Patented Oct. 11, 1938 UNITED STATES 2,132,525 e PORTABLE 'ADJUS'IABLEV CHAIR l-Iarold Burchalb Kingswood, England pplicationNovember 6, 1935, Serial No. 48,549

' `In Great Britain November 13, 1934 eclaims. (ci. s- 116)- This invention relates'to portable adjustable chairs and it has for its objects the construction of a chair (a) which will enable same to `be used so that the user may sit in an approximately up- 5 right position or in an/ approximately full reclning position or any desired position intermediate these two maximum, positions, the change of position, either up or down, being effected by the user without rising from the lchair by the operation of'acontrol device; (b) in .which the centre of gravity of the chair andits occupant remains within the base ofthe chair irrespective of the position of its component parts, thereby avoiding any tendency for the chair to tip in any direction throughout the range of its adjustment; (c) in which, as the inclination of the backV is increased, the entire seat and thek back -arejboth lowered towards the floor,.thereby enabling'the legs of the occupant to assume a more natural attitude in all positions, thatV is, when the chair is in the upright position the legs from the knees downward are in a more or less vertical position, but as the chair is gradually lowered intothe lowest position the legs more nearly approach a horizontal position; (d) in which, irrespective of any adjustments that may be made in the position of the seat and back of vktherchairfthe ibase does not vary and can be rigidly fixed to ythe floor; and (e) in which the chairmay befolded so as to occupy a space approximately equal to` the height ofthe rigid frame.

To attain these ends the chairv comprises a rigid framework, vertically-disposed supporting members hinged to the front of the-rigid frame, a seat frame pivoted to said vertically disposed supporting members, the rear partof said seat frame being arranged to slide on a runway forming part of or secured to the rigid framea v back frame pivoted adjacent its lower endy to the rear of the seat frame; means forv adjusting said seat and back frames relatively to the rigid frame and means for controlling and/or releasing the adjusting means when it is desired to vary the positionof the seat and back frames and means yieldingly connecting framev with the rigidframe serving to balance the weight of the moving parts and of 'the occupant, and also to assist in returningsaid moving parts to a higher andto normalposition when the adjusting means are released. v; A I

In the laccompranying drawings which illustrate one embodiment of the inventionz4 Figure 1 is a perspective view oi a lchair complete with leg rest and cushions; l -l I 1 Figure 2 is a side elevation, with the cushions removed, Vof a chairin the normal ror erect posi.- tion;

the chairy in the extreme extended position; I

Figure 4 is a plan of Figure 3, and, .l

the rear end of said seat` Figure 3, isla similar View to Figure v2 Vshowing e Figure the chair in the iolded'position.

Referring to the drawings, in the embodiment illustrated the various frame sections are built up of tubular members, identical in construction and comprise tworrigd L-shaped frames, each of which is composed o'ftwo members I and 2, the upper ends of the' vertical members I areconnected and spaced apart by a transverse member v3 andthe horizontal members 2 are connected` and spacedapart by a transverse member 4.v The'vertical and horizontal members I and 2 of eachy side frame are also stayed by a member 5 arranged at about 42, which stay member also forms a ramp for the purpose hereafter described. A vertical member 6 is connected by pivot pins 1 to each of the front ends of the horizontal other by a transverse member 8. `The extreme upper end of each of the members 6 is pivoted at 9 to a bracket I0 secured to a rectangular horizontally disposed frame comprising a transversely disposed member I I', anda pair of side'members I2, each of 'which is rigidly connected at its front end to the transverse member II land at'its rear end toa pair of triangular plates I3, the two pairs of plates being spaced apart and connected to each other by a transverse member I4. A short tubular member I5 is pivotally mounted between each of ther pairs of plates I3, said member I5 being arranged to slide onthe angularly disposed member 5. I

The back frame comprises twovertically disposed members I6, the extreme lower endsA of such members are pivotally connectedy to ,the

plates I3. The upper ends of the vertical members I5 are spaced apart and connected together by a transversely disposed member I1.

For the purpose of controlling the rise and fall of the seat and back frames, one end of an elastic cord I8 (composed of a plurality of strands of India-rubber suitablyV braided) is secured, as shown in Figure 3, between the plates I3 secured to the rear end of each of the side members I2 of the seat frame, each of said cords being carried upwardly and rearwardly over a pulley I9 mounted between a pair of plates to which the upper ends of the vertical members I and angularly disposed members 5 are rigidly connected, each of said cords pass downwardly through the tubular vertical members I around a pulley 2| mounted between a pair oi platesl 22 to which the lower ends of the vertical members I and the rear ends of the horizontal members 2 are rigidly connected, and through said members 2 to the front ends thereof where they are anchored in any convenient manner, such as by looping the end of the cord or a part secured thereto around the pivot pin connecting the members 2 and, 6,

both sides of the chair arey 5 is a similar view to Figure 2 showing i members] and to each n The means for adjusting and locking the seat frame in any desired position comprises a crossshaft 23 provided adjacent each end with a pair of lugs 24 by means of which said shaft is rockably mounted at 25 on the side members I2 of the seat frame; on each end of the cross-shaft 23 is secured a lever 26 arranged to slide in slots 21 provided in plates 28 secured to quadrants 29, the upper ends of which are hingedly connected at to members 3| constituting the arm rests for the chair; the rear ends of said arm rest members 3| are pivotally connected at 32 to a part 33 secured to or formed integrally with the vertical members I6 of the back frame which at this point are preferably provided with a second tubular member 34 as shown, and the ends of the levers 26 adjacent the cross-shaft 23 are connected to parts 35 on the rear ends of the arm rest members 3| by a pair of jointed links 36 pivoted to the levers 26 and parts 35 at 31 and 38 respectively. The lower ends of the quadrants 29 are hingedly connected at 39 to the front transverse member II of the seat frame. Suitable means are provided for locking the levers 26 relatively to the quadrant plates 28 and thereby the seat and back frame in any desired'positiom and, as shown, one edge of the slots 21 in the quadrant plates 28 is provided with notches 40 in which the levers 26 adjacent the operative ends thereofV are caused to engage, as shown` clearly in Figure 1. The cross-shaft 23 is further provided at each end with a downwardly depending member 4I, the lower ends of which are connected by links 42 to the vertically disposed members 6 at 43,

The chair may, if desired, be provided with a removable leg and foot rest composed of a pair of side members 44 spaced apart and connected together by a plurality of transversely disposed members 45; the upper ends of the side members 44 are provided with short members 46 adapted to be'removably attached by the pivot pins 9 to the upper ends of the members 6.

The spaces between the vertical side members I6 of the back frame, the side members I2 of the seat frame and the side member 44 of lthe leg rest may be lled in with canvas or like material 41 stretched taut by lacing or other means, thereby constituting a suitable support for the back and seat cushions 48 and 49 respectively and for the back of the legs in the case of the foot rest.

In use, assuming the Yseat of` the chair to be in its highest position, that is, practically horizontal as shown in Figure l, and that the person sitting thereon desires to rest in a more reclined position, the sitter takes hold of the knobs 50 on the operative ends of the levers 26, pulls same slightly inwardly and thereby re-releases said levers from the locking notches 46 in the quadrant plates 28,' the levers maythen be pushed forwardly and downwardly; the seat will then lower gently against the pull of the elastic cords, the action of said cords being balanced by the pressure on the handles and the weight of the occupant. When the desired position has been reached; for example, the extreme position shown in Figure 3, the sitter releases the levers 26 which due to the lateral bending of the levers instantly engage the locking notches 49 in the quadrant plates 28 thereby locking the seat and connected parts in the desired position. To return the seat to the highest position, or to a position intermediate the highest or lowest, the sitter releases the levers 26 from the locking notches 4U and pulls yheight of the folded chair, as shown in Figure 5,

being but slightly more than the height of the rigid frame.

It will be understood that if desired the framework of thev chair may be arranged to support two or more seats and said seats may be sepa- Vrately or independently controllable, or may be arranged tor act in unison with each other.

It will be obvious that the several frame sections may be formed in ways varying from that above described without departing from the essential characteristics of the invention according to the use to which the chair is to'be put. Further, the back frame of the chair may be provided with a frame 5I, the downwardly directed members of which are slidably arranged in the vertical members I6, being retained in any desired position by friction, adapted to support a head rest or pillow 52 with or without side wings 53 and the arm rest members 3| are preferably padded and provided with removable covers 54.

What I claim is:-

1. A portable adjustable chair comprising in combination a rigid frame, vertically disposed supporting members pivoted at their lower ends to the iront of said rigid frame, a seat frame pivotally connected to the upper ends of said vertically disposed supporting members, means pivotally mounted on the rear ends of said seat frame slidably connecting said seat frame with an inclined member of the rigid frame, a back frame pivoted at its lower end to the rear of the seat frame, means for adjusting said seat and back frames relatively to each other and vertically with respect to the rigid frame, means for securing said'adjusting means and thereby the adjustable parts of the chair in any desired position, and means yieldingly connecting the rear end of said seat frame with the rigid frame assist in returning said moving parts to a higher and to a normal position when the adjusting means is released, the lower ends of the vertically disposed supporting members being detachable from the front end of the rigid frame so as to permit the back frame to be folded down on to the top of the seat frame.

2.V A portable adjustable chair comprising in combination a rigid frame, inclined ramps provided on said frame, vertically disposed supporting members detachably pivoted at their lower ends to thefront of said rigid frame, a seat frame pivotally connected to the upper ends of said vertically disposed supporting members and slidably arranged at its rear on said ramps, a frame pivoted adjacent its lower end to the rear of the seat frame, means for adjusting said seat and back frames relatively to each other and vertically with respect to the rigid frame, means for securing said adjusting means and thereby the adjustable parts of the chair in any desired position, means yieldingly connecting the rear end of the said seat frame with the rigid frame serving to balance the weight of the moving parts and the occupant while the relative position of the parts is being changed and also to assist in drawing the seat frame upwardly and rearwardly up said inclined ramps "porting members pivoted to the front of said frame, a seat frame pivoted to the upper ends of said vertically disposed supporting members and slidably arranged at its rear endy on said ramps, a back frame pivoted adjacent its lower end to the rear of the seat frame, means providing an elastic connection between the seat frame and the rigid frame comprising an elastic cord arranged on each side of the chair connected to the seat frame and rigid frame, quadrant members pivoted at their lower ends to the front end of the seat frame, arm rest members pivoted at their rear ends to the back frame and at their front ends to the lupper ends of the quadrant members, a laterally extending plate secured to each of said quadrant members,'a longitudinally disposed slot provided in each of said plates, a plurality of stops provided in one edge of each of said slots, means for adjusting said seat and back frames relatively to the rigid frame comprising a cross-shaft secured to parts rockably mounted on the seat frame, a lever secured to each end of said cross-shaft, the operative ends of said levers being arranged to slide in the slots formed in the plates secured to the quadrant members and to coact with the stops provided therein, jointed links connecting the lower ends of said levers with the back frame, a downwardly directed member provided adjacent each end of said cross-shaft and links connecting said downwardly directed members to the vertically disposed supporting members.

4. A portable adjustable chair comprising in combination a pair of rigid side frames, an inclined ramp secured to each of said frames, a vertically disposed supporting member pivoted to the front of each side frame, a plurality of transversely disposed members rigidly connecting said side frames and supporting members, a rectangular seat frame pivoted to the upper ends of said vertically disposed supporting members and slidably arranged at its rear end on said ramps, a rectangular back frame pivoted adjacent its lower end to the rear of the seat frame, means yieldingly connecting the rear end of said seat frame with the rigid frame comprising an elastic cord arranged on each side ofthe chair connected to the seat frame and a rigid side frame, quadrant shaped members pivoted at their lower ends to the front end of the seat frame, arm rest members pivoted at their rear ends to the back frame and at their front ends to the upper ends of the quadrant shaped members, a curved laterally extending plate secured to each of said quadrant shaped members, a longitudinally -disposed slot provided in each of said plates, a plurality of stops provided in each of said slots, means for adjusting said seat and back frames relatively to the rigid frame comprising a cross-shaft secured to parts rockably mounted on the seat frame, a lever secured to each end of said cross-shaft, the operative ends of said levers being arranged to slide in the slots formed in the plates secured to the quadrant shaped members and to coact with the stops provided therein, jointed links connecting the lower ends of said levers with the back frame, a downwardly directed member secured adjacent each end of said cross-shaft and links connecting said downwardly directed members to the vertically disposed supporting members.

5. A portable adjustable chair comprising in combination a rigid frame, inclined ramps secured to said frame, vertically disposed supporting members pivoted at their lower ends to the front of said frame, a seat frame pivoted to the upper ends of said vertically disposed supporting members and slidably arranged at its rear end on said ramps, a back frame pivoted adjacent its lower end to the rear of the seat frame, means comprising an elastic cord arranged on each side of the rigid frame yieldingly connecting the rear end of said seat frame with the rigid frame, quadrant members pivoted at their lower ends to the front transverse member of the seat frame, arm rest members pivoted at their rear ends to the back frame and at their iront ends to the upper ends of the quadrant members, a laterally extending plate secured to cach of said quadrant members, a longitudinally disposed slot provided in each of said plates, a plurality of stops provided in each of said slots, means for adjusting said seat and back frames relatively to the rigid frame comprising downwardly directed lugs rockably mounted on the side members of the seat frame, a cross-shaft secured to said lugs, a leversecured to each end of said cross-shaft, the operative ends of said levers being arranged to slide in the slots formed in the plates secured to the quadrant members and to coact with the stops provided therein, jointed links connecting the lower ends of said levers with the back frame, a downwardly directed member secured adjacent each end of said cross-shaft and links connecting said downwardly directed members to the vertically disposed supporting members.

6. A portable adjustable chair comprising in combination a rigid frame, vertically disposed supporting members connected at their lower ends to the front ends of said rigid frame, a seat frame pivoted to the upper ends of said vertically disposed supporting members and slidably arranged at its rear end on inclined members on said rigid frame, a back frame pivoted to the rear of the seat frame, means for adjus'ting said seat and back frames relatively to each other and vertically with respect to the rigid frame, means for securing the adjusting means and thereby the adjustable parts of the chair in any desired position, means yieldingly connecting the rear end of said seat frame with the rigid frame serving 'to balance the weight of the moving parts and the occupant while the relative position of the parts is being changed and also to assist in returning the chair to normal position when the adjusting means is released, and removable pins connecting the vertically disposed supporting members to the rigid frame so that when the pins are removed the lower ends of said supporting members may be pushed rearwardly and the back frame folded down on to the top of the seat frame.

HAROLD BURCHALL. 

